This project investigates how socio-environmental conditions affect the psychological functioning of the elderly. It tests hypotheses about how, as one grows older, such social-structurally determined environmental conditions such as complexity affect cognitive functioning, autonomous self-directed orientations and one's feelings about oneself and one's circumstances. The data come from a follow-up survey of 707 respondents originally selected in 1964 as part of a nationally representative sample picked for an investigation of how occupational conditions affect psychological functioning. This year saw the completion of the laborious process of developing structural equation models for the major portion of the psychological variables and the most important of the occupational variables. In doing this a variety of different approaches were compared. These included making both separate and combined models for men and women and investigating whether the same measurement parameters could be applied to data collected at the three time points. The findings indicate that the psychological and occupational measurement models that were estimated over twenty years ago continue to be valid and reliable and that in most cases similar parameters can be used for data from both sexes and each time period. Initial causal models evaluating the reciprocal effects of complex occupational conditions and level of cognitive functioning were also estimated. In the course of doing so a variety of very complex statistical problems had to be understood and overcome. Although preliminary, the initial findings suggest that exposure to complex occupational conditions continues to increase intellectual flexibility as people age.